Hello there. I am looking for some help with my furnace.

I am a first-time homeowner with little experience with these things. There are a few things that I know for sure though. Starting with the fact that this furnace is way oversized for the 900 sqft single store home (plus basement).

I have attached a few photos of the unit and a few of the details are as follows:

1. In which area you live and ambient temperatures you usually experience. - Nova Scotia Canada
2. House style and construction details. - Wood Construction bungalow with unfinished basement.
3. Make, model and age of equipment related to the problem. - Attached Photos - LBO 105-DR
4. Fuel type. - Oil
5. Water temperature and pressures of boiler systems.
6. What type of zoning do you have with your boilersystem.
7. Thermostat type. - Nest Thermostat E
7. Anything else that would be useful. No detail is to small. The more information you provide the easier it becomes for the professionals in this forum to determined the cause and correction to the problem.

The issue I have is this, I have been gifted a Nest Thermostat E which I installed in place of the old thermostat, I confirmed using the Nest website that I was able to install the Thermostat and followed the instructions provided to install it. I hooked up all the available wires and everything seemed to be fine.

That is until the next day when I came back to the house to discover that the house was at 46 degrees C indoors. The furnace had been running none stop for about 12 hours. I have narrowed down the issue to the fact that the when the fan runs the burner starts at the same time. So when the thermostat was trying to cool the house by running the fan it was in fact just making the place hotter and hotter in a vicious cycle of heat. (I ran through about $100 worth of oil at that time).

I am able to run the fan independently of the burner via the use of the pullout button on the furnace itself. It makes zero sense to me that I am not able to run the fan from the thermostat without the burner running.

So my question is, is there an issue with my furnace, or is there an issue with the Nest compatibility/setup?

I should also mention that the photos are not quite up to date. The wiring in the later photo of the relay box is representative of the wiring in the nest on the other end.

Any input would be greatly appreciated, as information on the specific model of the furnace has been nearly impossible to come by.

Thanks in advance.

 

You need to post the up-to-date pictures of the thermostat and furnace wire connections. How was the old thermostat hooked up? With these systems normally there is no wire on the W.

Normally only 3 wires should be hooked up to the Nest:

Boiler R = Nest R
Boiler W = Nest no connection
Boiler Y = Nest no connection
Boiler G = Nest W1
Boiler C = Nest C

 

A recommendation......

Boiler R ------ red ------- nest R
Boiler G ------ white -----nest W1
Boiler C ------ blue ------ nest C

In your pictures you are showing as shorting W1 to common. That could have damaged the nest.

 

I forgot to answer one question. That furnace has a mechanical fan limit switch (behind white push/pull button) so does not have a provision to control the fan via a remote thermostat. Because of that neither a Nest or any other thermostat would give you fan control without modifying the furnace.

 

Thank you for your responses.

Sorry, it's taken a couple of days to reply. I have wired the best as per the recommendations given. All seems to be working correctly but I will keep a close eye on it.

That's for the clarification on the fan situation. It would be a massive pro to get it to the point that the fan runs independently but as its -12 outside I don't believe that is something I need to worry about for now.

I would post the updated photos but the wiring now represents the information you gave me so it would be a little redundant.

Thanks again for your help.
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It is do-able to be able to control the blower from your thermostat. It would take the addition of a 24vAC relay.

I would highly recommend an RIB relay to do what you want. It's cost effective and will mount directly to your existing fan center junction box. The RIB2401D is one particular model that will work. Shop around for a good price. If you decide you want to to do this...... get the relay and I'll tell you how to wire it. A very easy job.

RIB relay

 

Turn the power off. In your last picture is the fan/limit switch on top. Take the cover off. Take the fan center relay off the plate so we can see the wiring inside the box.

Please list what three wires you used from the nest to the fan center and the letter they are on.
Did you follow this....
Boiler R ------ red ------- nest R
Boiler G ------ white -----nest W1
Boiler C ------ blue ------ nest C

 

For the sake of completeness here are pictures of the current wiring and of the requested fan center relay.

 

White/yellow from relay to the C terminal on the fan center with the blue wire.
White/blue from relay to brown thermostat wire.
Yellow from relay to blue in fan/limit control.
Orange from relay to black wire in fan/limit control.
Cap or tape off unused wires - white/black, blue, purple, brown and gray.

Brown thermostat wire to G on nest.
You can attach to the fan center wires inside tje splice box behind the fan center transformer.

 

Okay, thanks very much. I will give this a go and let you know how I get on.

 

Hello DanSteve, I have the exact same Lincoln/Barriere furnace and a Riello F3 of the 40 Series oil burner. I got these new back in 1992 and they're still going strong. I also have a heat pump so the oil burner does not get to work very much in winter time season. Seeing your connections, I think you don't have A/C so like the recommandations you already received from expert users, you effectively only need 3 wires to operate your furnace but there is always an extra wire to operate the fan without the heat going on. Normally, this is wire G. You should check on your previous thermostat if there was provision for an extra lever to activate the fan. Seems to me it's been like that for decades so you should have an extra wire just for the fan. I also have a Nest 3rd gen Tstat. If I want to use the fan even though the furnace is not operating, I simply go in the parameters and activate the fan. If you want, you can program it to run let's say for 15 minutes every hour or even for 60 minutes every hour (which then means all the time) but that's an option on your Nest. Look in the instructions manual and you'll surely find it or better, simply go on your computer, click on the parameters icon on the top right corner and you'll see it going down the window.

Hope this helps you.

 

But don't you have an extra relay on the side of your furnace to operate the fan? Normally, there are 2 relays on this furnace, one for the burner (which you show) and another one for the fan. The relay operating the burner is a Honeywell R8405B and it needs to operate is a dry contact like you have on your Nest. The C post seems to be used only to supply a ground for the Nest to operate. But there's another relay on this furnace. Originally it was a Honeywell R4222D and it is connected to the fan and the fan limit control. On my furnace, it has been replaced by a second R8405B just for the fan. If you want, I can send you the wiring diagram of the furnace.

Best,

 

The OP has supplied us with many pictures. There is no second relay in view. On many oil fired furnaces..... you could get them as a straight oil furnace only or with the optional A/C preinstall package.

 

There may have been some straight oil furnace but this one is absolutely identical to mine and I'm pretty sure there is a relay for the blower. Here is the wiring diagram for this furnace and it sure shows a blower relay. Maybe a photograph of where the power line enters the furnace would clarify the situation.

Big Al

 

Hello, I am trying to set a similar Lincoln Barriere furnace on fan only mode using an Emerson thermostat that I just purchased. The old thermostat had just three wires, one unused. I tried connecting the spare wire to both G terminals without any result. This is a dual-energy furnace but I don't think it changes a thing. There is a on/off fan switch directly on the furnace. Could I use this switch + the RIB2401D relay + the unused wire to activate the fan from my thermostat? If yes, can someone give me the correct wiring? I'll be glad to provide pictures is needed. I like the challenge of this small DIY mission. Thank you

 

Hi, to give you a complete answer, we'd need to have more "meat", which is to say more infos on the wiring and terminals of the actual Tstat and the former one. PLS provide the brands and models of Tstats used on your installation. You can still use your furnace in fan only mode by simply depressing the white button on the relay of the furnace for the high speed and the manual rocker switch on the side for the low speed. When you'll submit pics of your installation, it will be possible to give you a more complete solution to your problem. BTW, the solution PJMax suggested to DanSteve was absolutely right according to the wiring diagram using the RIB2401D relay.

Big Al

 

Hello, here are some pictures of my system. The last image is a rear view of the manual fan switch on the furnace.I have included a generic image of my current Emerson thermostat terminals, disregard all the wires on the image as this is not my actual wiring. I am currently only using the RH (Red wire) and WE (Black wire). As mentioned earlier, I'd like to take the unused white wire to control the fan only mode. There has to be a way as I already have the possibility to turn on the fan using the manual switch. Thanks for your assistance, this is very helpful

 

This is a bit off topic I guess.....but still pertains to this type of furnace. Any ideas where to get gasket material that would be suitable for the exhaust flue plate at the rear of the furnace. Took mine off to clean out the heat exchanger and boy is it toast !

 

hi I am new to this type of furnace and am wondering where the filters go or are there any? Thx

 

Welcome to the forums.

Any filters used would go in the return line. You could have one large filter in a hallway behind a grill.
Look closely where the return duct joins the furnace.

 

I can see by the views that this is a hot topic.
However the thread has become too long and too many different problems and posters involved.
A new thread can be found here..... Lincoln-Barriere-LBO-105-DR-oil-furnace-questions.

Feel free to reference this thread if you start a new one or post in the newly started one.